Thank you Jim. That is exactly what I am trying to do by asking these questions.You need to diagnose the problem first, not throw parts at it and hope you come up with the fix.
It’s an electronic VR. I added a star washer just to be safe after reading some posts on herewhat kind of VR are you using, points or electronic?> Make sure the electronic has a good ground from its case to the firewall with a star washer as I believe the VR uses a variable ground to this mounting surface to vary the 'excitement' of the alternator.
This time with key turned to run but engine off. It read 11.84 at the battery, and 1.52 at the blue field wire at the alt. So I add those together and get 13.36? Or did I misunderstand that. Thanks again.
If you cannot easily fix voltage drop in the hot side of the harness, one way around it is to cut the blue "ignition run" wire coming out of the bulkhead at some point BEFORE it branches off. Use the end coming out of the firewall to trigger a Bosch relay, power the relay through a breaker / fuse from the starter relay stud, and hook the other cut end of the blue "IGN1" to the switched contact on the relay. This will then provide a solid voltage referenced to the battery for underhood loads, including the VR
No worries! After reading and rereading this thread as well as a couple other threads on here I removed and cleaned the bulkhead connectors and while they did need a good cleaning the issue remained. So I added the relay as you described and that did the trick! Much appreciated as always.I've been gone. Looks like you made progress!